Field of the Invention
The present invention relates generally to fluid delivery systems and in particular to a fluid delivery system and method for caging or storage systems for animals, such as ventilated laboratory rack systems.
Description of Related Art
A large number of laboratory animals are used every year in experimental research. These animals range in size from mice to non-human primates. To conduct valid and reliable experiments, researchers must be assured that their animals are protected from pathogens and microbial contaminants that will affect test results and conclusions. Proper housing and management of animal facilities are essential to animal well-being, to the quality of research data and teaching or testing programs in which animals are used, and to the health and safety of personnel.
Ordinarily, animals should have access to portable, uncontaminated drinking water or other needed nutrient containing fluids according to their particular requirements. Water quality and the definition of potable water can vary with locality. Periodic monitoring for pH, hardness, and microbial or chemical contamination might be necessary to ensure that water quality is acceptable, particularly for use in studies in which normal components of water in a given locality can influence the results obtained. Water can be treated or purified to minimize or eliminate contamination when protocols require highly purified water. The selection of water treatments should be carefully considered because many forms of water treatment have the potential to cause physiologic alterations, changes in microflora, or effects on experimental results. For example, chlorination of the water supply can be useful for some species but toxic to others.
Because the conditions of housing and husbandry affect animal and occupational health and safety as well as data variability, and effect an animal's well-being, the present invention relates to providing a non-contaminated, replaceable, disposable source of fluid for laboratory animals in a cage level barrier-type cage or integrated cage and rack system to permit optimum environmental conditions and animal comfort. The present invention also relates to cost-effective and hygienic systems for providing fluid to animals housed in cage and rack systems equipped with automatic water systems.
Animal suppliers around the world have experienced an unprecedented demand for defined pathogen-free animals, and are now committed to the production and accessibility of such animals to researchers. Likewise, laboratory animal cage manufacturers have developed many caging systems that provide techniques and equipment to insure a pathogen free environment. For example, ventilated cage and rack systems are well known in the art. One such ventilated cage and rack system is disclosed in U.S. Pat. No. 4,989,545, the contents of which are incorporated herein by reference, assigned to Lab Products, Inc., in which an open rack system including a plurality of shelves, each formed as an air plenum, is provided. A ventilation system is connected to the rack system for ventilating each cage in the rack, and the animals therein, thereby eliminating the need for a cage that may be easily contaminated with pathogens, allergens, unwanted pheromones, or other hazardous fumes. It is known to house rats, for example, for study in such a ventilated cage and rack system.
The increasing need for improvement and technological advancement for efficiently, safely housing and maintaining laboratory animals arises mainly from contemporary interests in creating a pathogen-free laboratory animal environment and through the use of immuno-compromised, immuno-deficient, transgenic and induced mutant (“knockout”) animals. Transgenic technologies, which are rapidly expanding, provide most of the animal populations for modeling molecular biology applications. Transgenic animals account for the continuous success of modeling mice and rats for human diseases, models of disease treatment and prevention and by advances in knowledge concerning developmental genetics. Also, the development of new immuno-deficient models has seen tremendous advances in recent years due to the creation of gene-targeted models using knockout technology. Thus, the desire for an uncontaminated cage environment and the increasing use of immuno-compromised animals (i.e., SCID mice) has greatly increased the need for pathogen free sources of food and water. One of the chief means through which pathogens can be introduced into an otherwise isolated animal caging environment is through the contaminated food or water sources provided to the animal(s).
Accordingly, the need exists to improve and better maintain the health of research animals through improving both specialized caging equipment and the water delivery apparatus for a given cage. Related caging system technologies for water or fluid delivery have certain deficiencies such as risks of contamination, bio-containment requirements, DNA hazardous issues, gene transfer technologies disease induction, allergen exposure in the workplace and animal welfare issues.
Presently, laboratories or other facilities provide fluid to their animals in bottles or other containers that must be removed from the cage, disassembled, cleaned, sterilized, reassembled, and placed back in the cage. Additionally, a large quantity of fluid bottles or containers must be stored by the labs based on the possible future needs of the lab, and/or differing requirements based on the types of animals studied. This massive storage, cleaning and sterilization effort, typically performed on a weekly basis, requires large amounts of time, space and human resources to perform these repetitive, and often tedious tasks.
Further, glass bottles (and the handling thereof) can be dangerous and also relatively costly. Bottle washing machines, bottle fillers, wasted water, hot water, wire baskets to hold bottles, sipper tubes, rubber stoppers, the ergonomic concerns of removing stoppers, screw caps insertion of sipper tubes are all problems inherent to the use of water bottles to provide water to animals.
With respect to automatic water systems, although automatic water systems are available, the cost per cage is too costly for many institutions. Traditionally, stainless steel valves and manifolds are used in automatic water systems and such parts require constant purging of slime and buildup of mineral deposits. Moreover, the stainless steel parts, such as the valves, require periodic repair. When repair is required, typically the institution must send the valves to the manufacturer to repair. This in turn requires that the institution maintain a second set of valves (and other parts that require periodic repair) to use while the first set of valves is being repaired. This adds significantly to the institution's costs.
The human factors of handling wire baskets while loading and unloading bottles has led to industry wide back injuries, carpel wrist injury, and eye injury from broken glass and other human factor ergonomic risks. By some estimates, the cost of injury related costs to industry and the lost productivity in the workplace amount to millions of dollars annually.
In addition, the use of water bottles typically leads to large energy costs because the cleaning of the water bottles typically requires hot water heated to approximately 180 degrees F. and the washing of all of the components of the water bottles and caps with dangerous chemicals.
Moreover, watering systems tend to fail due to time and/or use conditions, which endangers the laboratory animals and laboratory studies. For example, laboratory animals may cause bedding material to enter into watering valves, thereby jamming the valve. This either prevents water flow to the animal cage or, more likely, causes the valve to remain in the open (flow) position, which floods the cage, possibly causing animal death. Valves also deteriorate over time, which may cause water leakages to occur. Water leaks can endanger the laboratory animals and compromise a study because damp cages or damp materials around a cage can cause excessive humidity, which can cause hypothermia in the laboratory animals.
As such, a need exists for an improved system for delivering fluid to laboratory animals living in cage level barrier-type rack and cage systems. Specifically, there is a need to provide watering devices, systems, and methods that are cost effective, require minimal maintenance, are resilient to environmental factors, and that minimizes dangers to laboratory animals and laboratory studies.